The UN has urged European countries to come forward to contribute more troops for the peacekeeping force in Lebanon.

Deputy Secretary General Mark Malloch Brown thanked Asian nations for their firm commitment but added the force had to be "multilateral" in character.

The call came after Israel said it might be "inconceivable" to accept nations that denied its right to exist, such as Malaysia and Indonesia.

A 15,000-strong UN force is planned to police the truce in southern Lebanon.

Under the terms of the UN ceasefire resolution which ended the month-long conflict between Israel and Hezbollah, the expanded UN force should work alongside about 15,000 Lebanese troops to keep the peace.

France has agreed to lead the force if its mandate concerns are but its immediate pledge of only 200 extra troops is far smaller than expected.

"There's been different signals coming out of France," US President George W Bush said.

"We hope they send more."

Two senior UN envoys, Vijay Nambiar and Terje Roed-Larsen, have arrived in Beirut for talks on how the UN-brokered truce is being implemented.

Heavy Israeli air activity over Hezbollah's Bekaa Valley heartland early on Saturday has been reported by Lebanese sources.

It was not immediately clear if any air strikes had been made.

'Prudent' force

Mr Malloch Brown said the commitment of troops by Indonesia, Malaysia, Bangladesh and Nepal among others was "enormously helpful and a major contribution".

UN TROOP PLEDGES

France - leadership and 200 troops

Bangladesh - two battalions (up to 2,000 troops)

Malaysia - one battalion (up to 1,000 troops)

Indonesia - one battalion, an engineering company

Nepal - one battalion

Denmark - at least two ships

Germany - maritime and border patrols

Sources: UN diplomats

But he said the force should have a "multilateral character so that it enjoys the confidence of both sides".

French Defence Minister Michele Alliot-Marie warned that soldiers could not be told: "Look what's going on but you don't have the right to defend yourself or to shoot".

Mr Malloch Brown said the new force would not be "offensive", nor would it be asked to "attempt large-scale disarmament".

"Rather it is going to police the political agreement which triggers disarmament called for under the resolution," he said.

Use of force would only be exercised if combatants forcefully resisted a demand to disarm, Mr Malloch Brown said.

A 3,500-strong vanguard is planned to be in place in the next 10 days.

European powers have so far been reluctant to sign up but Italy on Friday confirmed it was approving sending troops to Lebanon.